This invention relates to coupling members that can be quickly latched together and disconnected, and more particularly to a novel coupling assembly that can be depressurized while the coupling members are latched together to permit safe and easy separation of the coupling members.
As used herein the terms "depressurize", "depressurization of the coupling assembly" and "depressurization of the coupling members" are intended to refer to a rapid loss of pressure by one of two coupling members.
Quick disconnect coupling assemblies afford instant utilization of a fluid supply source and allow the fluid supply source to be interconnected with different fluid outlets. Some fluid supply sources, such as pressurized gas tanks will cause a relatively high pressure buildup across the coupling members. Consequently, a quick disconnection of the coupling assembly usually results in a rapid depressurization of the coupling member that is disconnected from the fluid supply source. During such depressurization the coupling member which loses pressure has a tendency to "shoot away" from the other coupling member due to the forces generated when there is a rapid release of pressure.
Because of the risk of injury when one coupling member "shoots away" from another coupling member during disconnection of high pressure couplings, special techniques have been developed for safely disconnecting coupling assemblies that join with a high pressure fluid supply. Such techniques usually require a combination of strength and skill, thus limiting the handling of high pressure couplings to select individuals even though numerous other personnel may be qualified to operate other parts of a fluid flow system that incorporates the high pressure couplings.
One known structure for dealing with the problem of "shoot-away" couplings, as shown in U.S. Pat. No. 4,483,510, is a coupling assembly with a two-stage release mechanism for disconnecting the coupling members. During the first stage of release, a locking element is actuated to permit movement of one of the coupling members away from the other coupling member to an intermediate locked position. As the actuator returns to its original unactuated position, the movable coupling member shifts to a second locked position wherein depressurization can take place. A subsequent actuation of the locking element frees the moveable coupling member to permit disconnection from the coupling assembly.
Although depressurization occurs while the coupling members are locked together, the need to actuate the locking element more than once to accomplish a safe disconnection can be confusing because most coupling assemblies are separable with one actuation of an actuating mechanism.
Another known coupling assembly as shown in U.S. Pat. No. 4,541,457 requires unthreading of the coupling members after fluid flow has been shut off by a poppet valve in the coupling assembly. Although the coupling assembly depressurizes during the unthreading process, there is no quick disconnection of the coupling members.
It is thus desirable to provide a reusable, quick disconnect coupling assembly that can be depressurized with the coupling members latched together and requires only one actuation of a release mechanism to depressurize and separate the coupling members.